People along the U.S. Eastern Seaboard need to keep an eye on the weather forecast as they make their holiday plans. The National Hurricane Center says Tropical Storm Arthur is likely to become Hurricane Arthur by Thursday evening as it approaches the North Carolina coast. Along the way it could cause heavy rains and high winds from Florida's Atlantic coast up through Georgia and South Carolina.
While Arthur is building up strength, Weather Underground founder Dr. Jeff Masters says in his Wednesday morning blog entry that dry air could hold down the storm's intensity. “Arc-shaped bands of low cumulus clouds were racing away from the storm to the north of the center, indicating that dry air had gotten ingested into Arthur's heavy thunderstorms, creating strong downdrafts that were spreading out along the ocean surface. This process robs a tropical storm of moisture and energy, and means that Arthur has considerable work to do in order to moisten its environment before the storm can close off an eyewall and attain hurricane strength.”
While it's still tempting to focus on the wind speeds of a given storm, it's worth remembering that the greatest dangers may be some of the side effects of a storm, such as flooding, storm surge and rip currents, all of which may be in play as Arthur works its way up the coast.
In his morning discussion NHC forecaster Dr. Lixion Avila puts Arthur's top sustained winds at 50 knots on a northerly course at 6 knots. So far, the North Carolina coastline is only a tropical storm warning although that could quickly change if Arthur continues to gain strength or starts turning to the left of the current track. However, given that the NHC's major computer models are generating very similar courses and intensities, forecasters are saying that they have high confidence in the current projections.